1. Field
The present disclosure relates generally to inert gas welding. More particularly, the invention is directed to oxygen monitors for monitoring oxygen around a weld zone prior to and during an inert gas welding operation.
2. Description of the Prior Art
By way of background, inert gas welding is a species of arc welding in which the molten weld pool is shielded from atmospheric contamination and oxidation by bathing it with an inert gas, such as Argon, or a mixture of Helium and Argon. Popular examples of inert gas welding include TIG (Tungsten Inert Gas) welding and MIG (Metal Inert Gas) welding.
When welding together pipes and other enclosed structures using inert gas welding, it is important to purge the interior of the pipe or structure in the vicinity of the weld zone to prevent corrosion and the formation of oxides on the interior side of the weld pool. Purge dams are conventionally used for this purpose. For example, when butt-welding the ends of two pipe sections to form a consolidated pipe run, two purge dam structures are placed in the pipes, one in each pipe on either side of the weld zone. A purge gas can then be introduced into the area between the dams to displace the oxygen therein.
It is common to use an oxygen monitor to determine whether sufficient oxygen removal has taken place for welding operations to proceed. Historically, such oxygen monitors have been non-portable apparatus of relative large size. More recently, portable hand-held oxygen monitors have become available. Although the portability of such devices enhances ease of use, hand-held oxygen monitors typically lack one or more features, which limits their usability in the field.
It is to improvements in the design and operation of portable oxygen monitors that the present disclosure is directed.